I will present quantum sensing of short-range forces with a force sensor based on trapped atom interferometry. Ultracold atoms are first transported with a Bloch elevator close to the surface of a dielectric mirror before being trapped in a vertical lattice. Raman pulses are then used to split the atoms across different wells and recombine them, creating a Ramsey-type interferometer. The phase of the interferometer depends on the difference of potential energy between neighbouring wells, and thus to the force exerted on the atoms. The stability of the local force measurement reaches 3 10-28 N at 1s measurement time, and decreases down to about 4 10-30 N after a few hours of averaging. With this sensor, we measure an attractive force of order of 10-27 N when bringing the atoms at a few micrometers from the surface, larger than the expected Casimir Polder force of about 0.4 10-27 N. We attribute the difference to parasitic electric fields created by adsorbed atoms, which we characterize and model. Correcting for this effect, we put into evidence the Casimir Polder force below 20 µm.
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Franck Pererira Dos Santos
SYRTE, Observatoire de Paris-Université PSL, CNRS, Sorbonne Université, LNE (more)
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Measurement of short range forces with quectonewton stability
I will present quantum sensing of short-range forces with a force sensor based on trapped atom interferometry. Ultracold atoms are first transported with a Bloch elevator close to the surface of a dielectric mirror before being trapped in a vertical lattice. Raman pulses are then used to split the atoms across different wells and recombine… (more)